Abstract: An articulated mast for use in supporting a coiled tubing injector on a deck of a transport trailer and capable of accomplishing storage of the mast and the injector in a compact manner on the deck for transport on the one hand in conjunction with other equipment in drilling operations, and yet capable of ready deployment of the injector to an operative position above a well head on the other hand. The mast includes boom sections pivotally joined relative to each other for movement between a position in which the sections are folded one on top of the other on the deck to an extended position for holding the tube injector above the well head rear of the transport deck.